As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LT MAIN MOUNT DID NOT LOCK DOWN WITH OTHER GEAR. GREEN LIGHT STAYED OFF AND RED UNSAFE INDICATOR LIGHT ILLUMINATED FOR 15+ SECONDS. JACKED A/C PERFORMED GEAR SWING IAW CE560E M/M 32-01-00. LANDING GEAR HYD SYSTEM ADJ/TEST. GEAR SWING OPS CHECKED GOOD. SUSPECTED MOISTURE IN GEAR DOWN LOCK SWITCH. CLEANED DOWN LOCK SWITCH CONNECTOR PER CESSNA TECH REP. GEAR TRAVEL TIMES WITHIN LIMITS. 5 SECONDS AND 4 SECONDS EXTEND. OPS CHECKED GOOD.